An engine control system includes an engine calibration module that sets fuel injection timing based on one of N cetane number (CN) values, wherein N is an integer greater than one. A combustion noise module generates a combustion noise signal based on cylinder pressure in a compression ignition (CI) engine during combustion. A fuel quality determination module compares the combustion noise signal to N predetermined combustion noise levels corresponding to the N CN values, and that selects the one of the N CN values based on the comparison.

A storage device is configured to store a first mapping that receives, as an input, a first input variable including a cam phase variable on present and past phases of a cam, and output a pulsating variable on a pulsating component. The execution device is configured to acquire the first input variable and estimate the pulsating variable by applying the acquired first input variable to the first mapping. Therefore, it is possible to estimate the pulsating variable without providing a low-pressure fuel pressure sensor by estimating a fuel pressure variable by applying the first input variable to the first mapping.

A fuel pressure estimation system estimates a fuel pressure variable on a fuel pressure in a supply pipe for an engine apparatus including an engine having a fuel injection valve, and a fuel supply device having a fuel pump that supplies the fuel in a fuel tank to the supply pipe, and includes a storage device and an execution device. The storage device stores a first mapping that receives, as an input, first input variables including a pump variable, a consumption flow rate variable on a consumption flow rate of the fuel, and a property variable on a property of the fuel, and outputs the fuel pressure variable. The execution device acquires the first input variables and estimates the fuel pressure variable by applying the first input variables to the first mapping.

Exemplary embodiments include a method for analysis of fuel supplied to a combustion engine during operation of the engine. The method can include obtaining respective indications of a temperature of the fuel supplied to the engine and a density of the fuel supplied to the engine; deriving a temperature-adjusted fuel density based on the indicated density of fuel in dependence of relationship between the indicated temperature of the fuel and a predefined reference temperature; and deriving, based at least on the temperature-adjusted fuel density, a heating value that is descriptive of the amount of heat released during combustion of a predefined amount of the fuel.

A method for determining a quantity of fuel injected into a cylinder of an internal combustion engine including an injection rail includes:—measuring the pressure prevailing in the injection rail during fuel injection from the rail into a cylinder;—filtering the pressure measurement;—determining the relative minimum and maximum points of the filtered pressure curve;—insofar as a first (Pdrop1) pressure drop followed by a pressure rise and then a second (Pdrop2) pressure drop is identified, determining a physical quantity that makes it possible to characterize the first pressure drop and the second pressure drop; and—determining the quantity of fuel injected by applying the bulk modulus for the two pressure drops identified as a function of the temperature in the injection rail.

The present disclosure relates to a method for determining the methane index of a hydrocarbon-containing combustion gas mixture which has natural gas or biogas, having the steps: flowing the gas mixture through a measuring assembly; determining a first value of a first measurement variable related to a viscosity of the gas mixture; determining a second value of a second measurement variable related to a density of the gas mixture; determining a pressure value of the gas mixture, said pressure value belonging to the first value and the second value; determining a temperature value of the gas mixture, said temperature value belonging to the first value and the second value; and determining the methane index as a function of the first value, the second value, the pressure value, and the temperature value.

In a method, dynamic pressure oscillations in the intake tract or outlet tract of a respective internal combustion engine are measured during normal operation, and from these measured oscillations, a corresponding pressure oscillation signal is generated. A crankshaft phase angle signal is determined at the same time. From the pressure oscillation signal, an actual value of at least one characteristic of at least one selected signal frequency of the measured pressure oscillations in relation to the crankshaft phase angle signal is determined, and the current trimming of the intake tract is determined on the basis of the determined actual value, taking into consideration reference values of the corresponding characteristic of the respectively identical signal frequency for different trimmings of the intake tract.

A fuel filter monitoring method includes receiving pressure signals that are indicative of a pressure drop across at least one fuel filter of a fuel supply system configured to supply fuel to at least one fuel injector of an internal combustion engine and receiving a condition signal indicative of a condition of a fuel supply system, the condition signal being generated by one or more of a geographic location sensor, an altitude sensor, and/or a fuel temperature sensor. The method includes estimating a remaining life of at least one fuel filter of the fuel supply system based on the pressure signal and the condition signal and outputting a notification indicative of the estimated remaining life.

A system comprising a distribution grid (2) for a fuel, combustion engines (3), which are coupled with the distribution grid (2) and are configured to combust the fuel, and a computer system (4) comprising data connections (5) to the combustion engines (3) and a data storage device (6), wherein the computer system (4) is configured to receive engine operation parameters stemming from an operation of the combustion engines (3) at a first time and/or during a first time period via the data connections (5) and geographical data of the combustion engines (3) are stored in the data storage device (6), wherein the computer system (4) has a processor (7) which is configured to compute a prediction for at least one characteristic parameter of the fuel at a second time and/or during a second time period later than the first time and/or the first time period and with respect to a geographical location, and the computation of the prediction being based on the geographical data and the engine operation parameters of the combustion engines (3).

The present invention refers to a charge changing control device for a reciprocating engine, comprising at least one cam follower configured for being pivotably actuated around a pivot axis (P) upon rotational movement of a camshaft, and an adjustment unit configured for setting at least three different charge-changing modes of the device by translationally displacing the pivot axis relative (P) to a rotational axis (R) of the camshaft.